1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)comsat.8 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: src/libexec/comsat/comsat.8,v 1.6.2.4 2002/08/18 17:30:53 johan Exp $ 34.\" $DragonFly: src/libexec/comsat/comsat.8,v 1.3 2006/02/17 19:33:31 swildner Exp $ 35.\" 36.Dd August 9, 2002 37.Dt COMSAT 8 38.Os 39.Sh NAME 40.Nm comsat 41.Nd biff server 42.Sh SYNOPSIS 43.Nm 44.Sh DESCRIPTION 45.Nm Comsat 46is the server process which receives reports of incoming mail 47and notifies users if they have requested this service. 48.Nm Comsat 49receives messages on a datagram port associated with the 50.Dq biff 51service 52specification (see 53.Xr services 5 54and 55.Xr inetd 8 ) . 56The one line messages are of the form: 57.Pp 58.Dl user@mailbox-offset[:mailbox-name] 59.Pp 60If the 61.Em user 62specified is logged in to the system and the associated terminal has 63the owner execute bit turned on (by a 64.Dq Li biff y ) , 65the 66.Em offset 67is used as a seek offset into the appropriate mailbox file and 68the first 7 lines or 560 characters of the message are printed 69on the user's terminal. Lines which appear to be part of 70the message header other than the 71.Dq From , 72.Dq \&To , 73.Dq Date , 74or 75.Dq Subject 76lines are not included in the displayed message. 77.Pp 78If the 79.Em user 80specified is logged in to the system and the associated terminal has 81the group execute bit turned on (by a 82.Dq Li biff b ) , 83two bell characters (ASCII \\007) are printed on the user's terminal. 84.Pp 85If mailbox-name omitted, standard mailbox assumed. 86.Sh FILES 87.Bl -tag -width /var/mail/user -compact 88.It Pa /var/run/utmp 89to find out who's logged on and on what terminals 90.It Pa /var/mail/user 91standard mailbox 92.El 93.Sh SEE ALSO 94.Xr biff 1 , 95.Xr inetd 8 96.Sh HISTORY 97The 98.Nm 99command appeared in 100.Bx 4.2 . 101.Sh BUGS 102The message header filtering is prone to error. 103The density of the information presented is near the theoretical minimum. 104.Pp 105Users should be notified of mail which arrives on other 106machines than the one to which they are currently logged in. 107.Pp 108The notification should appear in a separate window so it 109does not mess up the screen. 110